Disk harrow



Au 6, 1929. o, A, K, P INTZ 1,723,576

DISK HARROW Filed May 16. 1928 F g Z 1' V 7 8 Patented Aug. 6, 1929.

UNITED STATES PATENT OFFICE.

OSCAR ADOLF KRISTIAN PRINTZ, 0F OVERUM, SWEDEN.

DISK HARROW.

Application filed May 16, 1828, Serial No. 278,317, and in Sweden January 19, 1927.

This invention relates to disk harrows adapted to be driven by tractors and. par ticularly to that type of disk harrow W 11011 is provided with two sets of disk gangs,

one behind the other, each set of gangs comprising two horizontally swingablc shafts withthcir groups of disks, one shaft at either side of the harrow. In such type of harrow it is usual practice to have the disk gangs so adjusted that the shafts of the forward gangs will form an obtuse angle With each other with the apex directed backwards while the shafts of the rearward gangs form an obtuse angle with the apex directed forwardly.

In order that the operator may readily control the adjustment of the disk gangs it has been already proposed to adjust both sets of gangs at a time by a common control mechanism. In such a case, however, angle of the forward shafts will, of course, be equal to that of the rearward shafts, though oppositely directed.

In practice, however, it has proved desirable in certain cases, in order to obtain a satisfactory effect, that the disks of one set of gangs may be adjusted to a different angle than the disks of the other set of gangs. To this end it has been already proposed to use individual controlling mechanisms for the forward and rearward sets of gangs, respectively. Such an arrangement presents several drawbacks. The op erator must always control two handles or cranks, even if the two sets of gangs are not adjusted to different angles and, furthermore, the handles or cranks will not be within easy reach of the operator, as one of them will come to lie within the other in order that both handles may lie at equal distance apart from the operators seat.

The object of this invention is to provide an improved controlling mechanism, including a single handle or crank by means of which all sets of gangs may be adjusted simultaneously and uniformly or one set may be adjusted to a different angle than the other set.

One feature of the invention resides in the combination with two separate controlling mechanisms, one for each set of gangs, of a single crank permanently connected to one controlling mecl'ianism and which may be coupled to the other controlling mechanism when desired.

Another feature relates to the pivotal connection between the frames carrying the forward and rearward gangs, respectively, and. resides in the provis1on of simple means to so connect said frames that the vertical or horizontal relative movements of said frames relatively to each other will have no effect upon the position of the two controlling mechanisms relatively to each other. i

i In the accompanying drawing one form of the invention is illustrated,

Fig. 1 is a plan view with the disk gangs shown in transverse ahnemcnt.

Fig. 2 is a side elevation ofthe parts as shown in Fig. 1. j r

Fig. 3 is a side elevation, on a larger scale, partly in section, of the crank of the controlling mechanisms and the associated clutch means. i

Fig. 4 is a plan view, likewise on a larger scale, of the connection between the front and rear frames.

With reference to the drawing, 11 in dicate the two diskcarryin shafts of the front disk gangs, and 22 indicate the disk carrying shafts of the rear diskgangs, The shafts 1, 1 are pivotally connected intermediate between their ends to the front draftframe 3 of the harrow, as shown at 4, and the shafts 2, 2 are similarly connected to the rear frame 5, as shown at 6. Each of the shafts 1, 1 carries a group of transversely spaced disks 7 and the shafts 2, 2 carry similar groups of disks 8. j

The rear frame is connected to the front frame 3 in a way enabling the frames to swing relatively to each other both horizontally and vertically. To thisend the rear frame 5 is connected by a vertical pivot, as

at 9, to a bracket 10, supported by the front frame by means of horizontal journals, as at 11, extending through upstanding cars 12 of said bracket and through men'ilziers 13 of the front frame. This will allow of relative swinging movement of the frames 3 and 5 relatively to each other both with respect to the vertical axis X-.X, Fig. 2,

and the horizontalaxis Y -Y, Figs. 1 and 4.

Pivotally connected to the shafts 1, 1 of the forward gangs near the inner ends thereof, as at 14, 14, are links 15., 15, pivoted at their opposite ends to levers 16, 16 pivoted at 17, 17 to the draft bar 18. The levers 16, 16 are pivoted to links 19, 19, pivotally connected at their other ends to opposite sides of a nut 20 mounted upon an exteriorly threaded hollow member 21 revolvably mounted. in a bearing 22. Formed on said hollow member 21 outside said bearing is a crank 23.

Extending through said hollow member 21 and revolvably supported therein is a shaft 24. The forward-end of said shaft, outside the forward end of the hollow mem ber 21, carries a collar 25. The other end of the shaft 24 is connected by a universal joint 26 to a shaft27 the rear end of which is threaded and engages a nut 28 carried by a air of levers 29, 29, pivoted to the rear] rame and connected at their other ends to links 30, 30 the other ends of which are pivotally connected at 31 to the inner ends of the rear disk carrying shafts 2, 2.

It is to be noted that the centre of said universal oint 26 coincides ,with the point of intersection of the axis X-X and Y-Y.

That portion of the hollow member 21 situated outside the bearing 22 is formed with longitudinally extending ears 32 at the side opposite the crank 23 between which an angularly shaped lever 33, 34 is revolvably mounted on the journal In register with the space between said cars 32 a longitudinal groove 36 is formed in the collar 25 to receive the end of the arm 33 of said lever 33, 34 when it is desired to lock the hollow member 21 with the crank 23 to the shaft .24. Normally, the arm 33 is held out of engagement with said groove. To this end the arm 34 carries a sliding pawl 37 which is acted upon by a spring 38 enclosed in a cap 39 secured to the arm 34 to serve as a handle therefor. Said wedgeshaped pawl 37 is adapted to engage either of two notches 40,41 formed in the upper edge of the ears 32'," as shown in Fig. 3. With the pawl 37 in engagement with the notch 40 the clutch arm 33 is in engagement with the groove 36 whereby the hollow member 21 is coupled to the shaft 24 so that both may be rotated as a whole by turning the crank 23. With the pawl 37 in engagement with the upper notch 41the clutch arm 33 is held out of engagement with the groove 36 so that only the hollow member 21 may be rotated by the crank 23. j

It is thus evident that,when it is desired to adjust the front and rear disk gangs simultaneously and uniformly, though in opposite directions, the handle 39 is operated so as to bring the pawl 37 into engagement with the groove 36. Should it then be desired to adjust the front gangs to different angles than the rear gangs this may be allowed by simply shifting the handle 39 to its 'upper position so as to bring the pawl 37 into engagement with the notch 41 be fore turning the crank 23.

It is evident that, when the harrow is in operation, the front and rear frames 3 and 5 perform relative movements relatively to each other both with respect to the horizontal and vertical axes X-X and Y-Y, respectively. Owing to the fact that such movements take place about a centre coinciding with the centre of the universal 'oint 26 it is seen that said movements will have no effect at all upon the connection between the shafts 24, 27, nor upon the relative positions of the shaft 24 and the hollow member 21. Any relative displacements of said parts are, therefore, avoided. This is an essential condition for the use of that simple type of clutch between the hollow member 21 and the shaft 24 as above described.

Vhat I claim is:

1. In a disk harrow the combination of two frames pivotally connected together, a pair of adjustable disk gangs carried by each frame, independent devices for adjusting each pair of disk gangs, including relatively rotatable shafts, one surrounding the other concentrically, a crank permanently connected to one of said shafts, and means to connect said crank to the other shaft and release it therefrom.

2. In a disk harrow the combination of two frames pivotally connected together, a pair of adjustable disk gangs carried by each frame, independent devices for adjusting each pair of disk gangs, including relatively rotatable shafts, one surrounding the other concentrically, a crank permanently connected to one of said shafts, a clutching pawl carried by one shaft, and means to bring said pawl into and out of engagement with the other shaft.

3. In a disk harrow the combination of a front frame, a rear frame pivotally connected to said front frame to turn relatively thereto about two axes at right angles to each other, adjustable disk gangs carried by each frame, means including a threaded shaft to adjust the gangs of the rear frame. another shaft, a universal joint connecting said two shafts, the centre of said universal joint coinciding with the point of intersection of said axes, means including a hollow threaded shaft to adjust the gangs of the front frame, said hollow shaft surrounding concentrically said other shaft, a crank permanently connected to said hollow shaft. and means to connect said crank to said other shaft and release it therefrom.

In testimony whereof I have signed my name.

OSCAR ADOLF KRISTIAN PRINTZ. 

